GB2032309A

GB2032309A - Transporting hot articles such as castings

Info

Publication number: GB2032309A
Application number: GB7928517A
Authority: GB
Original assignee: Arbed SA
Current assignee: Arcelor Luxembourg SA
Priority date: 1978-08-22
Filing date: 1979-08-16
Publication date: 1980-05-08
Also published as: IT1122839B; AU5007279A; FR2438227B1; US4314790A; SE7906822L; LU80145A1; AU531997B2; GB2032309B; SE437568B; CA1149349A; DE2900497C2; JPS5547316A; ATA555979A; IT7925215A0; FR2438227A1; NL7906234A; DE2900497A1; BE878275A

Description

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GB 2 032 309 A

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SPECIFICATION Transportation of hot articles

5 This invention relates to the transportation of hot articles such as hot metallic articles, particularly hot ingots and slabs, under reduced thermal loss.

The problem of transporting hot metallic articles under reduced heat loss arises whenever cast or 10 pre-rolled metallic articles have to be transported to remote facilities, either because of permanent local circumstances or in order to provide logistic support. The distances to be covered in such cases range from a few hundred metres to several kilometres. 15 Long distances give rise to the problem of loss in temperature and to the more serious problem of a progressive increase in the difference in temperature between the surface of the article and the core of the article.

20 Heating the articles to their initial temperature to make up for the losses due to transportation requires large amounts of energy and substantial lengths of time, especially when massive metal bodies like steel ingots or slabs are transported. Therefore, the 25 walls, bottom and lid of carriages used for transporting such articles have to be carefully insulated. The expensive heat-resisting insulators that are used for this purpose are stressed thermally as well as mechanically, especially when the carriage is loaded 30 or unloaded. Therefore, the carriages are equipped with replaceable insulating panels.

These facts raise the cost of hot metal articles transported over short or long distances, owing to the price of insulating materials and to the labour 35 involved.

According to the present invention, there is provided a method of transporting a hot article, which comprises fluidising a granulated or powdered insulating material in a container for the hot article by 40 means of a flow of gas whilst loading the hot article into the container, discontinuing the flow of gas when the hot article has been loaded into the container and allowing the insulating material to settle around the hot article, and transporting the hot 45 article in the container.

Preferably, there are used sufficient amounts of insulating material to assure that once the fluidising gas-flow is discontinued, the article is completely covered with insulating material.

50 In an embodiment of the invention, the insulating material is again fluidised during the unloading of the transported article.

In the method of the invention, the hot articles are surrounded by a layer of mobile insulating material, 55 on loading and on transporting. Fluidising the insulating material on loading has two advantages. Firstly, a dynamic medium is created inside the container, and the article can be introduced into this medium without difficulties and can be placed upon 60 the bottom of the container. Secondly, an article of any shape can be surrounded by an insulating material having a constant density and a constant heat transfer coefficient.

The degree of heat retention that can be attained 65 by the invention enables one to simplify the conventional means of insulation of the carriage walls and lid and to increase their life.

In a preferred embodiment, at least a part of the insulating material is pneumatically removed during fluidising, on loading or unloading. This step is especially advantageous during the unloading, because when at least part of the material has been removed, the crane operator obtains a clear sight of the article.

A preferred insulating material is porous vermicu-lite. The preferred materials have a low density, a mean particle size of 2-4 mm, a low heat transition coefficient and a high abrasion resistance.

The gas used to fluidise the insulating material may be any gas or gas mixture which under the given circumstances reacts neither with the hot article nor with the insulating material. Thus, air may be used as a fluidising agent when normal carbon steel is to be transported.

It will be appreciated that, in view of the advantages offered by the method, neither the price of the insulating material, of which only limited amounts are needed when good use is made of the space available in the container, northe costs of the fluidising operation, which is used only on loading and on unloading, will be disadvantageous.

The present invention also provides a device for use in the method of the invention, which device comprises a movable container provided with means for enabling a gas to flow into the container whereby the granulated or powdered insulating material which in use is contained in the container can be fluidised.

The device preferably comprises a container sitting on wheels and having a movable lid, the container being advantageously made of steel, its bottom being protected by a layer of refractory material in which there are set several gas-permeable inlets, and gas conduits for pressurised gas installed below the container bottom, which conduits are connected to the gas-permeable inlets.

The gas-permeable inlets may be of porous refractory sintered material, or of sintered metal, or they may be replaceable sheets or tubes of refractory steel, having minute holes. The container bottom preferably has longitudinal ribs along both sides of the gas-permeable inlets and extending above the inlets. These support the article, i.e. they prevent the latter from contacting the gas-permeable inlets.

They may be for example, rails, bars or refractory bricks. The gas conduits which are connected to the gas-permeable inlets can be embodied so as to form a carriage support, adding to its rigidity.

A preferred embodiment of the device has at least one pneumatic feeding pump fixed onto the carriage and at least one bunker, the feeding device being connected to the container and to the bunker in order to feed the granulated or powdered insulating material to and fro.

The movable lid of the container may be on rollers moving horizontally. Alternatively, several lids may be used. Owing to the degree of heat retention that can be attained, the lid is intended to prevent the insulating material from being blown out of the moving container and to keep the material dry,

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GB 2 032 309 A

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rather than to prevent loss of heat.

For a better understanding of the invention, reference will now be made, by way of example, to the accompanying drawing, the single Figure of which is 5 a cross-section view of a device of the invention when loaded and when the insulating material has settled.

Referring to the Figure, there is shown a steel container 20 on a wheeled support 10. Although the

10 latter is a railway carriage in this embodiment, it may also be designed to move on wheels other than railway wheels.

The bottom 21 of the container 20 has a refractory concrete layer 22 in which there are porous gas-

15 permeable inlets 23. The rails 24 which rest upon the bottom 21, alongside the inlets 23, prevent ingots 60 from contacting the inlets 23. The ingots 60 may be secured against tumbling with the help of side pieces.

20 Below the bottom 21 there is a gas conduit 30 adding to the rigidity of the wheeled support 10 and having an inlet pipe 31.

The container has a horizontally moveable lid 25 on rollers.

25 An insulating material 50 totally surrounds the ingots 60. The container has no special insulation apart from the refractory concrete layer 22. The walls and the lid may be provided with conventional insulating panels, especially when the ingots are to

30 be transported over long distances.

Claims

1. A method of transporting a hot article, which

35 comprises fluidising a granulated or powdered insulating material in a container for the hot article by means of a flow of gas whilst loading the hot article into the container, discontinuing the flow of gas when the hot article has been loaded into the

40 container and allowing the insulating material to settle around the hot article, and transporting the hot article in the container.

2. A method according to claim 1, wherein at least part of the insulating material is pneumatically

45 added to the container during loading of the hot article.

3. A method according to claim 1 or 2, wherein the transported hot article is unloaded from the container, and wherein the insulating material is

50 fluidised by means of a flow of gas during the unloading.

4. A method according to claim 3, wherein at least part of the insulating material is pneumatically removed from the container during the unloading of

55 the hot article.

5. A method according to any of claims 1 to 4, wherein the quantity of insulating material used is sufficient to completely cover the hot article once the flow of gas has been discontinued.

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6. A method according to any of claims 1 to 5, wherein the insulating material is porous vermicu-lite.

7. A method according to any of claims 1 to 6, wherein the insulating material has a mean particle

65 size of from 2 to 4 mm.

8. A method according to any of claims 1 to 7, wherein the gas is one which does not react either with the hot article or with the insulating material.

9. A method according to any of claims 1 to 8,

70 wherein the container is a steel container.

10. A method according to any of claims 1 to 9, wherein the hot article is a hot steel ingot or a hot steel slab.

11. A method according to claim 1, substantially

75 as hereinbefore described with reference to the accompanying drawing.

12. A device for use in the method according to claim 1, which device comprises a movable container provided with means for enabling a gas to flow

80 into the container whereby the granulated or powdered insulating material which in use is contained in the container can be fluidised.

13. A device as claimed in claim 12, wherein the means for enabling a gas to flow into the container

85 comprises a plurality of gas-permeable inlets provided in the bottom of the container and a gas conduit connected to these inlets.

14. A device as claimed in claim 13, wherein the inlets are porous, heat-resistent, sintered bricks.

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15. A device as claimed in claim 13, wherein the inlets are porous, heat-resistent, sintered metal plates.

16. A device as claimed in claim 13, wherein the inlets are plates of perforated, heat-resistent, steel

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17. A device as claimed in claim 13, wherein the inlets are heat-resistent steel tubes.

18. A device as claimed in any of claims 13 to 17, wherein the inlets are replaceable devices.

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19. Adevice as claimed in any of claims 13to 18, wherein the bottom of the container has thereon longitudinal ribs which extend alongsidetheinlets and which extend above the inlets.

20. Adevice as claimed in any of claims 13 to 19, 105 wherein the gas conduit is integral with the container to give rigidity thereto.

21. Adevice as claimed in any of claims 12 to 20, further comprising (a) at least one pneumatic feeding device and (b) at least one bunker, the feeding

110 device being connected to the bunker and to the container.

22. A device as claimed in any of claims 12 to 21, wherein the container is a steel container.

23. A device as claimed in any of claims 12 to 22, 115 wherein the bottom of the container is lined with a layer of concrete.

24. A device as claimed in claim 12, substantially as described with reference to, and as shown in, the accompanying drawing.

Printed for Her Majesty's Stationery Office by Croydon Printing Company Limited, Croydon Surrey, 1980.

Published by the Patent Office, 25 Southampton Buildings, London, WC2A1 AY, from which copies may be obtained.